Recent advances in the field of wireless communications integrated circuit design have resulted in the promise of much higher frequency and data rate broadcast capability at significantly reduced prices. Being developed are integrated circuits in which both radio and signal processing circuits for the millimeter wave spectrum of frequencies are placed on one integrated circuit chip.
Wireless transmission in the 60 GHz band (i.e., 57-65 GHz) has several advantages. First, this band is unlicensed by the Federal Communications Commission (FCC) in the United States, and moreover, the band is unlicensed in most of the rest of the world. Second, due to the extremely short wavelengths the use of this band requires a very small antenna which can be embedded in the same integrated circuit as the radio and signal processing circuitry. Moreover, very high data transmission rates can be achieved in the 60 GHz frequency range, including rates of the order of several gigabits per second (“Gbps”). This makes possible wireless transmission of very large quantities of data including, but not limited to, uncompressed, high definition television (HDTV) signals, the rapid wireless transmission of a high definition movie file to a portable device, or other useful high bandwidth applications.
The usefulness of very high wireless bandwidth is not limited to applications involving transmission distances of several meters, or more. In certain communication link applications, it is desirable that high bandwidth signals be wirelessly transmitted over relatively short distances, such as for instance, a distance of a couple of centimeters or less.
For example, high bandwidth transmission of data in a wireless mode can be advantageous where there exist many wires or data transmission paths leading to one transmitter (such as for example, 32 wires for one transmitter), to reach a high data rate of 1 Gbps channel, for example. Thus when 32 signals are sent in parallel for multiplexing into a 1 Gbps channel that is transmitted serially, a wireless transmission can provide bandwidths that are superior to that which may be achieved via wired connections between a data source and a sink. What is important in certain applications, therefore, is not the distance a wireless signal travels, but rather the bandwidth of such a wireless signal. Thus a 1 or 2 cm transmission distance (or less) would be acceptable. This also provides a degree of isolation between the transmitter and receiver.
Digital communications, entertainment, and business uses have evolved such that ever increasing bandwidth requirements continue. Although the bandwidth associated with a millimeter wave frequency signal is relatively large, it nevertheless is desirable to achieve ultra-high bandwidth capabilities of hundreds of Gbps or more, using the millimeter wave spectrum of frequencies.